POPLAR BLUFF, Mo. (AP) — Health officials say mosquitoes in the Poplar Bluff area have tested positive for the West Nile virus.

Butler County Health Department officials told The Poplar Bluff Daily American Republic that the mosquitoes that tested positive were found in mid-October in a trap set as part of a surveillance program. The health department conducts the testing annually.

The county did not find West Nile-positive mosquitoes in 2010, but officials say it’s not unusual for Butler County to have at least one vial returned positive during the year.